Selection of patients with ovarian cancer who may show survival benefit from hyperthermic intraperitoneal chemotherapy: A systematic review and meta-analysis

BACKGROUND: The use of hyperthermic intraperitoneal chemotherapy (HIPEC) after cytoreductive surgery has been extensively studied in patients with peritoneal carcinomatosis from various malignancies. However, the effectiveness of HIPEC for ovarian cancer is still controversial. Therefore, we performed this meta-analysis to identify patients with ovarian cancer who can obtain survival benefit from HIPEC. METHODS: Articles regarding HIPEC in the MEDLINE, EMBASE, and Cochrane Library were searched till December 2018. In total, 13 case-control studies and two randomized controlled trials were included in this meta-analysis. We investigated the effect of HIPEC on disease-free survival (DFS) and overall survival (OS), and performed subgroup analyses based on the study design, adjustment of confounding variables, and quality of the study. RESULTS: HIPEC improved both DFS (hazard ratio [HR], 0.603; 95% confidence interval [CI], 0.513–0.709) and OS (HR, 0.640; 95% CI, 0.519–0.789). In cases of primary disease, HIPEC improved DFS (HR, 0.580; 95% CI, 0.476–0.706) and OS (HR, 0.611; 95% CI, 0.376–0.992). Subgroup analyses revealed that HIPEC did not improve OS but improved DFS of patients with residual tumors ≤1 cm or no visible tumors. In cases of recurrent disease, HIPEC was associated with better OS (HR, 0.566; 95% CI, 0.379–0.844) but not with DFS. Subgroup analyses also revealed similar tendencies. However, HIPEC improved DFS of patients with residual tumors ≤1 cm or no visible tumors, while it improved OS of only those with residual tumors ≤1 cm. CONCLUSIONS: HIPEC may improve DFS of patients with ovarian cancer when residual tumors were ≤1 cm or not visible. It may also improve OS of only patients with recurrent disease whose residual tumors were ≤1 cm.